A nitrogen-doped residue-based porous carbon supported platinum catalyst, its preparation method and application

Abstract

The present invention discloses a nitrogen-doped residue-based porous carbon supported platinum catalyst, a preparation method thereof and an application thereof. The present invention uses cheap and easily available petroleum residue as a carbon source, and synthesizes nitrogen-doped residue-based porous carbon by a simple template-assisted and nitrogen-doping modified calcination method. Using this carbon material as a carrier, platinum nanoparticles with good dispersion and an average particle size of 1.4-1.8 nm are in-situ prepared, and the platinum (111) crystal plane has the characteristic of lattice compression. Attributed to the strong interaction between the small-sized platinum nanoparticles and the nitrogen-doped residue-based porous carbon carrier, which hinders the agglomeration of platinum and causes lattice compression, resulting in the downward shift of the d-band center. When the catalyst prepared by the present invention is applied to the oxygen reduction reaction, it exhibits excellent activity and stability, and its mass specific activity can reach 370 A / g Pt , and the mass specific activity only loses 17.9% after 30,000 cycles of ADT cycling.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and particularly relates to a nitrogen-doped heavy oil-based porous carbon supported platinum catalyst, a preparation method thereof, and an application thereof. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) are one of the most promising energy conversion devices, in which highly active Pt is an indispensable catalytic element for the oxygen reduction reaction (ORR) in PEMFCs. At present, the activity and stability of commercially available Pt / C catalysts need to be further improved, and the scarce resources and high price of Pt seriously hinder their wide application. Based on the above problems, it is necessary to rationally design and controllably synthesize catalysts to maximize the utilization of Pt.

[0003] Adjusting the electronic structure of the catalyst is one of the effective strategies to improve the electrocatalytic ORR activity of metals. Usually, methods such as alloying and constructing core-shell structures are used to achieve the crystal lattice modulation of Pt, resulting in the shift of the d-band center relative to the Fermi level, thereby changing the chemical adsorption strength of ORR intermediate products to improve the catalytic activity. However, there are few studies on directly achieving the crystal lattice modulation of Pt nanoparticles through carbon carriers at present.

[0004] Vulcan XC-72 carbon black, as the most widely used Pt / C carrier in commercial applications, usually has problems such as weak binding force with Pt nanoparticles and easy corrosion of itself, thus affecting the activity and service life of the catalyst. Therefore, it is of great research significance and application prospect to develop a carbon carrier with low cost, large-scale preparation, and strong interaction with supported Pt to synergistically improve the activity and stability of Pt. Heavy oil, as a by-product of crude oil development, mainly exists in the form of polycyclic aromatic hydrocarbons and has a rich carbon content. At present, functional carbon materials synthesized from heavy oil have shown great application potential in the fields of energy storage, non-noble metal catalysis, adsorption separation, etc. The research on petroleum-based carbon as a carrier for loading noble metals, especially Pt nanoparticles, remains to be further developed and improved. Summary of the Invention

[0005] The object of the present invention is to use cheap petroleum residue as a carbon source to prepare a nitrogen-doped porous carbon support for loading platinum nanoparticles, and to provide a highly active and highly stable nitrogen-doped residue-based porous carbon supported platinum nanoparticle catalyst (Pt / N-PPC), its preparation method and application. The carbon source adopted in the present invention is cheap and easily available, has a high carbon content and has many aromatic rings. After carbonization, the formed carbon support and the small-sized platinum nanoparticles loaded on the surface have a strong interaction, which can effectively inhibit the aggregation of platinum nanoparticles and improve their stability. More importantly, this carbon support derived from residue-based also induces lattice compression of the (111) crystal plane of the platinum nanoparticles loaded on the surface, further regulating the catalytic activity of the platinum nanoparticles. The catalyst provided by the present invention exhibits excellent ORR activity and mass-specific activity, and also shows good application potential in the application of proton exchange membrane electrodes.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] The present invention provides a nitrogen-doped residue-based porous carbon supported platinum catalyst. The catalyst uses petroleum residue as a carbon source and iron(III) oxide as a template. After high-temperature calcination and acid etching treatment, a porous carbon material is prepared. Then, using urea as a nitrogen source, secondary high-temperature calcination is carried out to prepare nitrogen-doped residue-based porous carbon. The obtained material is used as a carbon support and dispersed in ethylene glycol. After adding chloroplatinic acid for in-situ reduction, Pt / N-PPC is prepared. The specific surface area of the carbon support is 500-600 m 2 / g, the pore diameter is 25-35 nm, the pore volume is 1.8-2.5 cm 3 / g, the relative content of nitrogen doping is 1.8-5.2 wt%; the average particle size of the loaded platinum nanoparticles is 1.4-1.8 nm, and its (111) crystal plane has the characteristics of lattice compression. The total mass of the platinum nanoparticles accounts for 7-34 wt% of the mass of the catalyst.

[0008] The present invention also provides a preparation method of a nitrogen-doped residue-based porous carbon supported platinum catalyst, including the following steps:

[0009] (1) Disperse petroleum residue in petroleum ether, add iron(III) oxide under rapid stirring, and continuously stir for 2-4 h. Use a rotary evaporator to remove the excess solvent to obtain a solid mixture. After grinding the above mixture, heat it in argon or nitrogen at a rate of 3 °C / min to 250-350 °C for calcination, and keep it warm for 45-80 min. Then continue to heat it at a rate of 3 °C / min to 700-900 °C for carbonization, and the holding time is 100-150 min. Finally, add the carbonized product to hydrochloric acid solution and let it stand overnight to remove the template. After washing to neutral, drying and grinding, a residue-based porous carbon material (PPC) is obtained;

[0010] (2) Weigh the residual oil-based porous carbon obtained in step (1) and disperse it in absolute ethanol. Dissolve urea in deionized water. Mix the above two solutions and stir for 1 - 4 h. After the solvent is evaporated to dryness, grind it and place it in argon or nitrogen. Heat it to 700 - 900 °C at a rate of 5 °C / min and calcine it for 100 - 150 min to obtain nitrogen-doped residual oil-based porous carbon material (N-PPC).

[0011] (3) Weigh the nitrogen-doped residual oil-based porous carbon obtained in step (2) and ultrasonically disperse it in ethylene glycol. Slowly add 2 - 9 mL of aqueous chloroplatinic acid solution dropwise. After adjusting the pH to 13 with aqueous sodium hydroxide solution, stir and reflux it in an oil bath at 100 - 150 °C for 2 - 5 h. When cooled to 85 °C, add hydrochloric acid as a precipitation promoter to adjust the pH to 3. After reaching room temperature, wash it until neutral. Finally, dry the product overnight and then grind it to obtain nitrogen-doped residual oil-based porous carbon supported platinum catalyst (Pt / N-PPC).

[0012] Furthermore, in step (1), the mass concentration of the petroleum ether solution of petroleum residue oil is 0.02 - 0.04 g / mL, the mass concentration of the petroleum ether solution of the template agent is 0.08 - 0.16 g / mL, and the mass ratio of the residue oil to the template agent is 1:4; the concentration of the hydrochloric acid solution is 1 - 3 mol / L.

[0013] Furthermore, in step (2), the mass concentration of the residual oil-based porous carbon ethanol solution is 0.01 - 0.03 g / mL, the mass concentration of the urea aqueous solution is 0.14 - 0.42 g / mL; the mass ratio of the carbon source to the nitrogen source is 1:3 - 1:7.

[0014] Furthermore, in step (3), the mass concentration of the nitrogen-doped residual oil-based porous carbon ethylene glycol solution is 1 - 2.5 mg / mL, the mass concentration of the aqueous chloroplatinic acid solution is 8 - 12 mg / mL, the concentration of the sodium hydroxide solution is 0.5 - 2 mol / L, and the concentration of the hydrochloric acid solution is 0.5 - 2 mol / L.

[0015] The present invention also provides the application of the nitrogen-doped residual oil-based porous carbon supported platinum catalyst in ORR and fuel cells.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1. The petroleum residue oil carbon source adopted in the present invention is cheap and easily available, has a high carbon content, and has many aromatic rings. Nitrogen-doped porous carbon is synthesized by using a simple template-assisted and doping modification calcination method, and the carbon carrier is cheaper and can be prepared on a large scale.

[0018] 2. The nitrogen-doped residue-based porous carbon synthesized in the present invention has a strong interaction with the surface-loaded Pt nanoparticles. The Pt nanoparticles loaded on this carbon support have good dispersibility and small average particle size, which can significantly improve the utilization rate of Pt. At the same time, the lattice of the (111) crystal plane of the Pt nanoparticles loaded on its surface is compressed, shortening the Pt-Pt bond length, resulting in the downward shift of the d-band center of Pt, weakening the adsorption of oxygen-containing intermediates. Therefore, Pt / N-PPC exhibits excellent ORR catalytic activity, with high mass-specific activity and good long-term stability, far superior to commercial Pt / C. Description of the Drawings

[0019] Figure 1 Figure 1 is the transmission electron microscopy (TEM) image of Pt / N-PPC prepared in Example 1.

[0020] Figure 2 Figure 2 is the particle size distribution diagram of Pt / N-PPC prepared in Example 1.

[0021] Figure 3 Figure 3 is the high-angle annular dark-field scanning transmission (HAADF-STEM) image of Pt / N-PPC prepared in Example 1.

[0022] Figure 4 Figure 4 is the X-ray diffraction (XRD) pattern of Pt / N-PPC prepared in Example 1 and commercial Pt / C.

[0023] Figure 5 Figure 5 is the X-ray photoelectron spectroscopy (XPS) pattern of Pt 4f of Pt / N-PPC prepared in Example 1 and commercial Pt / C.

[0024] Figure 6 Figure 6 is the linear sweep voltammetry (LSV) test pattern of Pt / N-PPC prepared in Example 1 and commercial Pt / C in O 2 saturated HClO 4 solution (0.1 mol / L). Test method: Weigh 2 mg of the catalyst and disperse it in 1 mL of deionized water and 10 μL of Nafion solution (5 wt%). After ultrasonic treatment for 40 min, the catalyst ink is prepared. 20 μL of the catalyst ink is uniformly coated on the glassy carbon electrode by the method of rotary drying as the working electrode, and Ag / AgCl and platinum sheet (1 cm 2 ) are used as the reference electrode and the counter electrode respectively. First, cyclic voltammetry (CV) activation scanning is carried out at a scanning rate of 100 mV / s in O 2 saturated HClO 4 solution (0.1 mol / L) for 40 cycles, and the scanning range is 0 - 1.2 V vs. RHE. Subsequently, the working electrode rotates at a speed of 1600 rpm, and in O 2 saturated HClO4 LSV tests were carried out in a solution (0.1 mol / L) at a scanning rate of 10 mV / s.

[0025] Figure 7 For the Pt / N-PPC prepared in Example 1 in O 2 Saturated HClO 4 (0.1 mol / L) before and after 30,000 cycles of accelerated cyclic stability test (ADT). The LSV curves are shown in Fig. Detailed implementation mode

[0026] In order to enable those skilled in the art of the present technology to better understand the technical solutions of the present invention, the above embodiments are only a part of the present invention and are used to help understand the present invention, and should not be regarded as specific limitations on the present invention.

[0027] Example 1:

[0028] (1) Weigh 2.5 g of petroleum residue and disperse it in 80 mL of petroleum ether. Then add 10 g of iron(III) oxide under vigorous stirring and continue stirring for 3 h. Use a rotary evaporator to remove the excess solvent to obtain a solid mixture. After grinding the above mixture, place it in argon. First, heat it to 300 °C at a rate of 3 °C / min and keep it warm for 60 min. Then continue to heat it to 800 °C at a rate of 3 °C / min, and the holding time is 120 min. Finally, place the carbonized product in a 2 mol / L hydrochloric acid solution and let it stand overnight to remove the template. After washing to neutral, dry and grind to obtain PPC.

[0029] (2) Weigh 0.4 g of residue-based porous carbon material and ultrasonically disperse it in 20 mL of absolute ethanol. Subsequently, dissolve 2 g of urea ultrasonically in 10 mL of deionized water. Mix the above two solutions and stir for 3 h. After evaporating the solvent, grind and place it in argon. Heat it to 800 °C at a rate of 5 °C / min, and the holding time is 120 min, then grind to obtain N-PPC.

[0030] (3) Weigh 80 mg of nitrogen-doped residue-based porous carbon and ultrasonically disperse it in 40 mL of ethylene glycol. Slowly add 4 mL of an aqueous solution of chloroplatinic acid with a concentration of 10 mg / mL. Adjust the pH to 13 using a 1 mol / L aqueous sodium hydroxide solution. Subsequently, stir and reflux in an oil bath at 130 °C for 3 h. When cooled to 85 °C, add 1 mol / L hydrochloric acid as a precipitation promoter to adjust the pH to 3. After cooling to room temperature, wash to neutral. Finally, dry the product overnight and grind to obtain Pt / N-PPC.

[0031] From Figure 1 the TEM, it can be seen that Pt nanoparticles are uniformly dispersed on N-PPC without obvious agglomeration. Using the same particle size statistical analysis ( Figure 2) It can be seen that the average particle size of the Pt nanoparticles is 1.6 ± 0.2 nm. Figure 3 For the HAADF-STEM characterization of Pt / N-PPC, compared with the standard lattice data of the commercial Pt / C catalyst, the (111) crystal plane of Pt / N-PPC has the characteristic of lattice compression. From Figure 4 it can be seen that the characteristic diffraction peaks of Pt are observed at 40°, 46°, 68° and 82° for the Pt / N-PPC catalyst, corresponding to the (111), (200), (220) and (311) crystal planes of Pt, respectively. Among them, the full width at half maximum of the Pt(111) peak of Pt / N-PPC is higher than that of the commercial Pt / C catalyst, indicating that the particle size of Pt / N-PPC is smaller than that of Pt / C. In addition, it can also be observed that the (111) crystal plane of Pt / N-PPC shifts to a higher angle, verifying again that the Pt nanoparticles supported on the N-PPC carrier have the characteristic of lattice compression. Figure 5 The Pt 4f binding energy of Pt / N-PPC was compared with that of the commercial Pt / C. The Pt 4f peak of Pt / N-PPC shifted positively by 0.5 eV, which was attributed to the transfer of electrons from Pt to the N-C carrier, indicating a strong metal-support interaction. From Figure 6 the LSV curve, the corresponding onset potential (E 0 ) and half-wave potential (E 1 / 2 ) data can be read. The E 0 and E 1 / 2 of Pt / N-PPC are 1.05 V and 0.905 V, respectively, which are better than those of the commercial Pt / C (E 0 = 1.03 V, E 1 / 2 = 0.881 V). At the same time, the mass activity (MA) and specific activity (SA) of Pt / N-PPC were also calculated, which were 370 A / g Pt and 720 μA / cm 2 , respectively, which are 3.34 and 3.38 times that of the commercial Pt / C, showing excellent ORR activity. From Figure 7 it can be seen that the half-wave potential of Pt / N-PPC only shifted negatively by 7 mV before and after 30,000 ADT cycles, which is also better than that of the commercial Pt / C catalyst (after 20,000 cycles, the half-wave potential shifted negatively by 40 mV). In addition, the MA and SA of Pt / N-PPC decreased by 17.9% and 9.7%, respectively, while the MA and SA of the commercial Pt / C decreased by 50% and 47.3%, indicating that Pt / N-PPC has excellent stability.

[0032] Example 2:

[0033] (1) Weigh 1.6 g of petroleum residue and disperse it in 80 mL of petroleum ether. Then, add 6.4 g of iron(III) oxide under vigorous stirring and continue stirring for 2 h. Use a rotary evaporator to remove the excess solvent to obtain a solid mixture. Grind the above mixture and place it in argon. First, heat it to 250 °C at a rate of 3 °C / min and keep it warm for 45 min. Then, continue to heat it to 700 °C at a rate of 3 °C / min and keep it warm for 100 min. Finally, place the carbonized product in 1 mol / L hydrochloric acid solution and let it stand overnight to remove the template. After washing to neutrality, dry and grind it to obtain PPC.

[0034] (2) Weigh 0.4 g of residue-based porous carbon material and ultrasonically disperse it in 20 mL of absolute ethanol. Subsequently, ultrasonically dissolve 1.2 g of urea in 10 mL of deionized water. Mix the above two solutions and stir for 1 h. After evaporating the solvent, grind it and place it in argon. Heat it to 700 °C at a rate of 5 °C / min and keep it warm for 100 min, then grind it to obtain N-PPC.

[0035] (3) Weigh 80 mg of nitrogen-doped residue-based porous carbon and ultrasonically disperse it in 80 mL of ethylene glycol. Slowly add 2 mL of an aqueous solution of chloroplatinic acid with a concentration of 8 mg / mL. Adjust the pH to 13 using 0.5 mol / L aqueous sodium hydroxide solution, and then stir and reflux in an oil bath at 100 °C for 2 h. When cooled to 85 °C, add 0.5 mol / L hydrochloric acid as a precipitation promoter to adjust the pH to 3. After cooling to room temperature, wash it to neutrality, and finally dry the product overnight and grind it to obtain Pt / N-PPC.

[0036] Example 3:

[0037] (1) Weigh 3.2 g of petroleum residue and disperse it in 80 mL of petroleum ether. Then, add 12.8 g of iron(III) oxide under vigorous stirring and continue stirring for 4 h. Use a rotary evaporator to remove the excess solvent to obtain a solid mixture. Grind the above mixture and place it in nitrogen. First, heat it to 350 °C at a rate of 3 °C / min and keep it warm for 80 min. Then, continue to heat it to 900 °C at a rate of 3 °C / min and keep it warm for 150 min. Finally, place the carbonized product in 3 mol / L hydrochloric acid solution and let it stand overnight to remove the template. After washing to neutrality, dry and grind it to obtain PPC.

[0038] (2) Weigh 0.4 g of residue-based porous carbon material and ultrasonically disperse it in 20 mL of absolute ethanol. Subsequently, ultrasonically dissolve 2.8 g of urea in 10 mL of deionized water. Mix the above two solutions and stir for 4 h. After evaporating the solvent, grind it and place it in nitrogen. Heat it to 900 °C at a rate of 5 °C / min and keep it warm for 150 min, then grind it to obtain N-PPC.

[0039] (3) Weigh 80 mg of nitrogen-doped residue oil-based porous carbon and ultrasonically disperse it in 32 mL of ethylene glycol. Slowly add 9 mL of an aqueous solution of chloroplatinic acid with a concentration of 12 mg / mL. Adjust the pH to 13 using an aqueous solution of sodium hydroxide with a concentration of 2 mol / L, and then stir and reflux in an oil bath at 150 °C for 5 h. When cooled to 85 °C, add 2 mol / L hydrochloric acid as a precipitation promoter to adjust the pH to 3. After cooling to room temperature, wash until neutral, and finally dry the product overnight and grind to obtain Pt / N-PPC.

[0040] Example 4:

[0041] (1) Weigh 2.5 g of petroleum residue oil and disperse it in 80 mL of petroleum ether. Then add 10 g of iron(III) oxide under vigorous stirring and continue stirring for 3 h. Use a rotary evaporator to remove the excess solvent to obtain a solid mixture. Grind the above mixture and place it in argon. First, heat it to 300 °C at a rate of 3 °C / min and hold for 60 min. Then continue to heat it to 800 °C at a rate of 3 °C / min, and the holding time is 120 min. Finally, place the carbonized product in a 2 mol / L hydrochloric acid solution and let it stand overnight to remove the template. After washing until neutral, dry and grind to obtain PPC.

[0042] (2) Weigh 0.4 g of residue oil-based porous carbon material and ultrasonically disperse it in 20 mL of absolute ethanol. Then ultrasonically dissolve 2 g of urea in 10 mL of deionized water, and mix and stir the above two solutions for 3 h. After evaporating the solvent, grind and place it in argon, heat it to 800 °C at a rate of 5 °C / min, and the holding time is 120 min, then grind to obtain N-PPC.

[0043] (3) Weigh 80 mg of nitrogen-doped residue oil-based porous carbon and ultrasonically disperse it in 40 mL of ethylene glycol. Slowly add 9 mL of an aqueous solution of chloroplatinic acid with a concentration of 10 mg / mL. Adjust the pH to 13 using an aqueous solution of sodium hydroxide with a concentration of 1 mol / L, and then stir and reflux in an oil bath at 130 °C for 3 h. When cooled to 85 °C, add 1 mol / L hydrochloric acid as a precipitation promoter to adjust the pH to 3. After cooling to room temperature, wash until neutral, and finally dry the product overnight and grind to obtain Pt / N-PPC.

[0044] To test the performance of the catalyst under actual PEMFC operating conditions, the Pt / N-PPC catalyst synthesized in Example 4 was used for H 2 -O 2Single cell system test of fuel cell. Test method: Spray catalyst ink onto Nafion 211# membrane (5 cm × 5 cm) to prepare membrane electrode assembly (MEA), where the anode is sprayed with commercial Pt / C (Pt content is 40 wt%), and the cathode is sprayed with Pt / N-PPC (Pt content is 29 wt%). The Pt loadings of the cathode and anode are 0.2 and 0.1 mg / cm 2 . The measurement temperature is 70 °C, and H 2 with 100% humidity and O 2 are introduced into the anode and cathode respectively, with a flow rate of 400 mL / min. Before the test, the membrane electrode needs to be activated to thoroughly activate the catalyst. After the fuel cell system is stable, the power density of the single cell is measured to be 866 mW cm -2 , indicating that Pt / N-PPC has good practical application performance.

[0045] In summary, a nitrogen-doped residue-based porous carbon supported platinum catalyst for oxygen reduction reaction and cathode application of proton exchange membrane fuel cell was prepared. As an ORR catalyst, Pt / N-PPC effectively improves the activity and durability of ORR. At a voltage of 0.9 V, the specific activity and mass activity of Pt / N-PPC reach 0.72 mA / cm 2 and 370 A / g Pt respectively. In addition, the prepared Pt / N-PPC catalyst has good application potential in the working environment of PEMFC, and the power density can reach 866 mW / cm 2 as the cathode catalyst. The excellent activity and stability are attributed to the high active area of small-sized Pt nanoparticles, the lattice compression of Pt(111) crystal plane, and the strong interaction between Pt and the carrier caused by nitrogen doping, which enhances the activity and stability of the catalyst.

[0046] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A platinum catalyst supported on nitrogen-doped residue oil-based porous carbon, characterized in that: Using petroleum residue oil as the carbon source and iron(III) oxide as the template, a porous carbon material is prepared by high-temperature calcination and acid etching treatment. Then, using urea as the nitrogen source, nitrogen-doped residue oil-based porous carbon is prepared by secondary high-temperature calcination. The obtained material is dispersed in ethylene glycol as a carbon support, and chloroplatinic acid is added for in-situ reduction to obtain a platinum nanoparticle catalyst supported on nitrogen-doped residue oil-based porous carbon (Pt / N-PPC); the average particle size of the supported platinum nanoparticles is 1.4 - 1.8 nm, and its (111) crystal plane has the characteristic of lattice compression.

2. The platinum catalyst supported on nitrogen-doped residue oil-based porous carbon according to claim 1, characterized in that: The average pore diameter of the carbon support is 25 to 35 nm, the pore volume is 1.8 to 2.5 cm 3 / g, the specific surface area is 500 to 600 m 2 / g, and the relative nitrogen doping content is 1.8 to 5.2 wt%; the total mass of the supported platinum nanoparticles accounts for 7 to 34 wt% of the mass of the catalyst.

3. A preparation method of the platinum catalyst supported on nitrogen-doped residue oil-based porous carbon according to claim 1, characterized by comprising the following steps: (1) Preparation of porous carbon material: Ultrasonically dissolve petroleum residue oil and iron(III) oxide templating agent in petroleum ether. After continuous stirring, use a rotary evaporator to remove the excess solvent to obtain a solid mixture. Grind the mixture and place it in an inert gas for high-temperature calcination to obtain a carbonized product. Add the carbonized product to hydrochloric acid solution and let it stand overnight to remove the template. Wash it to neutral, dry and grind to obtain residue oil-based porous carbon material (PPC); (2) Preparation of nitrogen-doped porous carbon material: Disperse the residue oil-based porous carbon material prepared in step (1) in absolute ethanol, and dissolve urea in deionized water. Mix and stir the above two solutions, evaporate the solvent to dryness, grind and place it in an inert gas for high-temperature calcination to obtain nitrogen-doped residue oil-based porous carbon (N-PPC); (3) After ultrasonically dispersing the nitrogen-doped residue oil-based porous carbon obtained in step (2) in ethylene glycol, slowly dropwise add an aqueous solution of chloroplatinic acid. Adjust the pH to 13 with an aqueous solution of sodium hydroxide, then stir and reflux in an oil bath. When cooled to 85 °C, add hydrochloric acid as a precipitation promoter to adjust the pH to 3. After reaching room temperature, wash it to neutral. Finally, dry the product overnight and grind it to obtain a platinum catalyst supported on nitrogen-doped residue oil-based porous carbon (Pt / N-PPC). (4) According to the preparation method described in claim 3, characterized in that: In step (1), the mass concentration of the carbon source petroleum ether solution is 0.02 - 0.04 g / mL; the mass concentration of the templating agent is 0.08 - 0.16 g / mL, and the mass ratio of residue oil to templating agent is 1:

4. The stirring time is 2 - 4 h; the inert gas is argon or nitrogen. First, heat it at a heating rate of 3 °C / min to 250 - 350 °C, keep it warm for 45 - 80 min, then continue to heat it at a rate of 3 °C / min to 700 - 900 °C, and the holding time is 100 - 150 min; the concentration of the hydrochloric acid solution is 1 - 3 mol / L. (5) According to the preparation method described in claim 3, characterized in that: ​ In step (2), the mass concentration of the porous carbon ethanol solution is 0.01 - 0.03 g / mL; the mass concentration of the urea aqueous solution is 0.14 - 0.42 g / mL, the mass ratio of the carbon source to the nitrogen source is 1:3 - 1:7, and the stirring time is 1 - 4 h; the inert gas is argon or nitrogen, heated to 700 - 900 °C at a rate of 5 °C / min, and the heat preservation time is 100 - 150 min.

6. According to the preparation method described in claim 3, it is characterized in that: In step (3), the mass concentration of the nitrogen-doped residue oil-based porous carbon ethylene glycol solution is 1 - 2.5 mg / mL; the mass concentration of the chloroplatinic acid aqueous solution is 8 - 12 mg / mL, and the dropping volume is 2 - 9 mL; the oil bath temperature is 100 - 150 °C, and the reflux time is 2 - 5 h; the concentration of the sodium hydroxide solution is 0.5 - 2 mol / L; the concentration of the hydrochloric acid solution is 0.5 - 2 mol / L.

7. Application of the nitrogen-doped residue oil-based porous carbon supported platinum catalyst described in claim 1 as a cathode catalyst for oxygen reduction reaction (ORR) and proton exchange membrane fuel cells (PEMFCs).

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